Vehicle climate control systems typically consume more energy than any other non-drivetrain system in modern vehicles. This is due to the need to defrost and/or to defog the windshield to maintain safe operation of the vehicle. It is also due to the desire to heat or to extract heat from the passenger cabin as quickly as possible to minimize the amount of time passengers are subjected to the discomfort of extreme cabin temperatures.
Most vehicle climate control systems rely primarily on blowing large volumes of conditioned air, i.e. heated and/or cooled air, into the passenger cabin until the overall cabin temperature is sufficiently comfortable for the passengers. The conditioned air is usually blown into the passenger cabin through vents located in and/or around the instrument panel or dashboard at the front of the vehicle.
Some vehicle climate control systems that include additional duct work routed throughout the vehicle have been proposed to more evenly distribute the conditioned air to second or third passenger seating rows, where the intended effect is generally to change the overall cabin temperature in a more uniform manner with little or no regard for energy consumption.
German patent publication DE 10 2008 052 019 A1 by Daimler AG discloses a vehicle seat with an air supply vent located on the seat back so that heated air can be blown on the back of a seat occupant's neck. The vent is installed in the seat at a fixed location and provides only heated air, useful to provide warmth to the seat occupant's neck for comfort, particularly in open-cabin vehicles such as convertibles.